"Honoured to represent my country, disappointed to run so poorly on the biggest stage," Rooney wrote on Twitter. "I moved on quickly from the Europeans and the main goal this season was to make the final here in Rio, I tried to come into the race as relaxed as possible and it showed, too slow through 200m is something that you can't do at this level.

"Hopefully Matt (teammate Matthew Hudson-Smith) can do the business and make the final. Apologies for my language post race, I need to sort out my head out for the relay and deliver for the guys when I'm needed."

He'll have a few days to think about his no-show performance. The 4x400m relay is scheduled for Friday, August 19.